Question

Two tables.
I have column a (datetime type) and column b (numeric type) in both tables.
I want to search column a in both tables and get ONLY the non matching ones.
Then display only the column a and b that do not have a matching datetime column a.

    Select Column b from Table 1 
    left join Table 2
    where Table1.Column a <> Table2.Column a

Is this correct??

Answer 1

You can use a left join as indicated by @drjay or a NOT IN clause. Personally I prefer the NOT in as it is easier to read.

SELECT [Column b] 
FROM [Table 1]
WHERE [Column a] NOT IN (
    SELECT [Column a]
    FROM [Table 2]
)